With rapid development of a communications network, the number of service categories, for example, mobile, voice, video, network games, and network browsing, is increasing, and the bandwidth is required to be higher. To transport a service such as a time division multiplexing service, the communications network must perform complex service classification, and simplify a processing process of a switching device, to improve processing efficiency and quality of the switching device.
FIG. 1 is a schematic diagram of a transport apparatus in the prior art. The transport apparatus in the prior art includes a receiving line card, a sending line card, and a switching unit. The receiving line card further includes a GMP (Generic Mapping Procedure, generic mapping procedure) demapping unit. The sending line card further includes a GMP mapping unit. For a received higher-order optical channel data unit (Optical channel Data unit, ODU) service, the GMP demapping unit demaps a bandwidth-variable ODUflex frame in the higher-order ODU service by using the generic mapping procedure, and sends the ODUflex frame to the switching unit. The switching unit interconnects, by using an inter-board bus, non-Ethernet switching units that are constructed. The switching unit sends the received ODUflex frame to the sending line card. The GMP mapping unit in the sending line card maps the received ODUflex frame and encapsulates the received ODUflex frame into the higher-order ODU service, and sends the higher-order ODU service.
In the prior art, the ODUflex frame cannot be transported by using an Ethernet switching unit, and the transport apparatus in the prior art cannot achieve compatibility in an Ethernet switching network.